The general idea is that the curation system works and works better if you vote for posts that you like, even if toy just started and don't have more than 3 SP. However even though it works at the start you will not be able to earn much. The idea here is probably so that when the user sees that he/she will want to purchase some additional power and at just 10 SP things are moving much better, though rewards are still not much, at least the chances are you might be actually getting something other than moral satisfaction for voting for the good posts.

I really hate it when people just upvote posts that they have not read, may not even agree or like what the author posted, but since he is popular and his post will get on the trending they are hoping that they can get a piece of the pie. Yes, they may get a tiny bit worth pretty much nothing in the end, but they are "feeding" people that may actually not deserve to get their vote. It is people acting just like bots, without thinking themselves and this is a mindless thing as they don't seem to easily give up even though they may not get anything in return... they continue trying.

It is simply much better, even if you are here just for the rewards, to try and post something interesting or good, doesn't matter what and that could bring you much higher reward if some people actually like it and vote for it...